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Offline Dday7

  • GS Junior Member
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  • Posts: 6
  • Bike: '19 BMW F750 GS
  • Town / City: Idaho
  • Country: us
Rear brake metal sensor tab
« on: July 23, 2020, 01:13:33 AM »
Howdy, I have a question about replacing the metal tab on the rear brake arm.

I don't have a manual so I don't know the actual name of it, I'll do my best to describe it and it's function:

The spring loaded metal tab that initiates the brake light...the rear brake pedal is stepped on and the metal tab behind the brake pedal arm pops up...or the spring is able to unload, pushing the small metal tab off it's seated position...which then causes the brake light to turn on. As best I can figure and understand.

In any case, that metal tab and spring disappeared in some Idaho mud a few miles back and the issues caused thus far are as follows:

1. The brake light doesn't turn on when you step on the brake.
2. You can't use cruise control because of the error message.
3. A constant warning triangle and error message regarding a faulty brake system turns on every time you ride and the triangle w exclamation mark stays on all the time.

Does anyone know how to get a replacement tab and spring? Part numbers and where to purchase online?

They seem flimsy, is there a better option out there? More durable, less prone to getting pulled off in heavy mud?

Thanks,
Eric




Offline Dday7

  • GS Junior Member
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  • Posts: 6
  • Bike: '19 BMW F750 GS
  • Town / City: Idaho
  • Country: us
Re: Rear brake metal sensor tab
« Reply #1 on: July 23, 2020, 01:58:59 AM »
What I've learned so far:
Part name = Brake Light Switch  or  Brake Light Switch Foot Brake
Part number = 61318562126
Price = $40.42 + tax & shipping

url for part purchase = https://www.shopbmwmotorcycles.com/p/73234959/61318562126.html

What I'm still wondering:
1. Can I pull the part and fabricate my own tab and spring to fix the problem?
2. Is it possible to purchase an OEM spring and tab without the rest of the assembly?

Offline talh

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  • Town / City: San Jose, CA
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Re: Rear brake metal sensor tab
« Reply #2 on: July 24, 2020, 08:31:18 AM »
So I just had to replace my rear brake switch (and the brake pedal itself) after crashing against a rock while dirt-riding .
You can't replace the tab - it's a single part, the whole switch. You might be able to cut a piece of aluminum and make do, but I wouldn't recommend it.

Note that it is held together by two metal pins that are just pushed in ($3.40 each pin). I managed to pry the old switch out with a flat-head screwdriver and re-used the old pins (with some thread-locker).
To take the switch off and put a new one on, the manual tells you to remove the entire plate - long process that involves taking parts of the swingarm apart. Don't do that. Pry the old switch out and save the pins. Start them in and use a long pliers and squeeze the pins home. It helps if you take the pedal off first.

I can give you the instructions and diagrams from the shop manual if you need them.

Offline Dday7

  • GS Junior Member
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  • Posts: 6
  • Bike: '19 BMW F750 GS
  • Town / City: Idaho
  • Country: us
Re: Rear brake metal sensor tab
« Reply #3 on: July 25, 2020, 08:44:44 AM »
Thanks for your response.
That would be awesome to have the diagrams and instructions from the manual.
Thank you for sharing your experience on how to replace the switch, I'll try to do the same.
I also sent you a pm if that's easier.
Eric